Previously, a technique mechanical processing a surface roughly on a metal implant to promote the osseous bonding force (U.S. Pat. No. 5,876,453) and further a technique producing the implant surface roughly by chemically etching a surface by blasting using ceramic particles or using a mixture of sulfuric acid and hydrochloric acid (U.S. Pat. No. 5,603,338) are disclosed.
According to a recent reference (Sul PhD thesis, Gothenburg Univ. Sweden 2002), a technique promoting a biochemical bonding by improving the chemical components of the implant surface is required, than metal implants free from said background art, i.e. a morphological improvement of the implant-surface.
As for improving the chemical components of the implant surface, a method melting ceramic particles at high temperature and injecting the melted ceramic on the implant surface so as to reform a Osseo-inductive surfaces (U.S. Pat. No. 4,145,764), and a method pressing a living-active ceramics particle such as a hydroxyapatite on the implant surface (JP-A 2001-00452), a method initiating ceramics which similar to bone components on a titanium implant surface (JP-A 1993-05703), a method forming a calcium titanate layer to improve binding ability outside implants and forming a calcium phosphate layer with excellent bone bonding force on the layer (JP-A 1993-057012), a method performing a thermal spray coating with a bio-compatible calcium phosphate on the implant surface and performing both pressurized water and polarization treatment (JP-A 2003-325553), and the like are already disclosed.